Bar-none, the Algenist retinol is the one that you want.
I JUST finished my RetASphere and am a big fan of many of Kate's products. I like her retinol formula quite a bit, but Algenist, frankly, blows it out of the water. (*Literally, after the second day of the 10-Day Challenge, I was won-over.) I write reviews and Q&As when I am truly passionate about a new product, regardless of the brand...this is something special. Hope you try it and love it as much as I have.
answered 6 months ago
I have tried both and I have to say I saw more results and recieved more compliments while using kate somerville. I purchased PTR retinol PM and I am not liking it at all I did give this a try and saw no difference at all but I did with the kate retashere product so i think I will be exchanging it tomorrow. I can honestly say that I recieved many compliments on my skin while on kate and not while using algenist or PTR and with PRT I feel like its doing more damage than good.